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U+1D409

MATHEMATICAL BOLD CAPITAL J

General category
Uppercase Letter Lu
Unicode block
Mathematical Alphanumeric Symbols
Combining class
0
Bidirectional class
L
Mirrored
No
Decomposition
<font> 004A

U+1D409 MATHEMATICAL BOLD CAPITAL J is a Unicode 16.0.0 character in the Uppercase Letter category. It belongs to the Mathematical Alphanumeric Symbols block.

Encodings & representations

Choose the representation you need, then copy its value.

Code point

U+1D409

Decimal value

119817

HTML decimal reference

&#119817;

HTML hexadecimal reference

&#x1D409;

UTF-8 bytes (hex)

F0 9D 90 89

UTF-16 code units (hex)

D835 DC09

UTF-32 code unit (hex)

0001D409

URL percent-encoded UTF-8

%F0%9D%90%89

C# Unicode escape

\U0001D409

JavaScript Unicode escape

\u{1D409}

JSON Unicode escape

\uD835\uDC09

CSS Unicode escape (trailing space)

\1D409
About these encodings
  • ASCII positions run from 0 to 127. Position cards show the decimal byte value followed by hexadecimal.
  • “Extended ASCII” is not a single encoding. ISO-8859-1 (Latin-1) and Windows-1252 are shown separately; they differ at bytes 128–159. Windows-1252 leaves five of those bytes undefined.
  • Legacy position cards appear only when the character has an exact mapping. For example, the euro sign is Windows-1252 byte 128 (0x80), but has no ASCII or Latin-1 position. A legacy byte is not necessarily the Unicode code point or its UTF-8 encoding.
  • Percent encoding lists every UTF-8 byte; URL-safe characters do not normally need encoding.
  • JSON escapes omit the surrounding quotes.
  • UTF code units are not byte-order-specific.
  • HTML parsers remap numeric references for U+0000 and some control characters, so these may not round-trip.